Chalk sharpening machine



Nov. 29, 1938. D. 5. GOLD CHALK SHARPENING MACHINE Filed Dec. 16, 1937 INVENTOR Dal 1d 6. Gold ATTORNEY Patented Nov. 29, 1938 ATET OFFICE CHALK SHARPENING MACHINE David S. Gold,

Brooklyn, N. Y.

Application December 16, 1937, Serial No. 180,104 7 4 Claims.

This invention relates to new and useful improvements in a chalk sharpening machine.

The invention has for an object to construct a machine as mentioned which is capable of sharpening tailors chalk. It is proposed to so arrange the machine that a piece of chalk may be engaged therein, and then a handle or other ccntrolling mechanism operated to cause the machine to sharpen the edge of the chalk. Still further the invention proposes to provide the machine with a box-like body having a slot in the top wall through which the piece of chalk may be held, and to provide a sharpening mechanism within the box.

Still further it is proposed to provide a drawer or a slide for the box-like body for collecting the shavings of chalk.

Another object of the invention resides in the specific construction of the cutting mechanism for sharpening the chalk.

Still further the invention proposes to so construct the mechanism mentioned in the previous paragraph that it is possible to adjust the same to sharpen the chalk with different kinds of sharp edges.

For further comprehension of the invention, and of the objects and advantages thereof, reference will be had to the following description and accompanying drawing, and to the appended claims in which the various novel features of the invention are more particularly set forth.

In the accompanying drawing forming a material part of this disclosure:

Fig. 1 is a perspective view of a device constructed according to this invention.

Fig. 2 is a sectional view taken on the line 22 of Fig. 1.

Fig. 3 is a horizontal sectional view taken on the line 3-3 of Fig. 2.

Fig. 4 is a perspective view of certain portions of the device, particularly the knife and means which supports the knife.

Fig. 5 is a bottom view of Fig. 4.

Fig. 6 is a fragmentary sectional view taken on the line 66 of Fig. 4.

Fig. '7 is a fragmentary sectional view taken on the line l'l of Fig. 5.

Fig. 8 is a perspective View of a piece of tailors chalk showing one type of edge sharpened there- Fig. 9 is a fragmentary end elevational view of a piece of tailors chalk sharpened with another type of edge.

The chalk sharpening machine comprises a box-like body I0 having a slit II in its top wall m through which a piece of tailors chalk, indicated by the dot and dash lines 12" in Fig. 2, may be held. A knife holding carriage I3 is slidably mounted within the body I0 and beneath the slot i i and supports a knife M for sharpening the edge of he chalk. A means is provided for moving the carriage Hi. The chalk shavings are adapted to fall down and be collected in a drawer l5 which extends from one of the walls of the box IE so that it may be pulled out and emptied when required.

The top wall it of the body is removably held in position by several screws H5 or other fastening elements. The carriage l3 comprises a slide it to'whicha foundation strip [3 is secured. This slide and foundation strip are arranged parallel to the slot l3. They are slidably' held in this. parallel position by several tracks i8 fixedly mounted upon the bottom face of the top wall lil The carriage I3 also includes a knife support strip l-Zi which is also disposed parallel to the foundation strip lii and is held in the parallel position by a pair of arms l3 (see Fig. 5). Each of these arms are pivotally held upon the foundation strip W and the knife support strip I3 by pintle screws E9. The arrangement is such that the knife support strip i3 may be moved to various parallel positions with respect to the foundation strip, for example, to the position indicated by the dot and dash lines l3 in Fig. 5.

The knife 54 is mounted upon the knife support' strip IS This knife comprises an L-shaped metallic piece having a vertical arm I l? formed with a V-shaped slot M The knife also has a horizontal arm [4 which is set into a recess 20 formed in the top face of the strip l3. The V-shaped opening It extends downwards and communicates with a V-shaped groove 2| formed in the top face of the knife support stripl3. The arrangement is such that when a piece of chalk is engaged into the V-shaped cutting portion of the knife it will be correspondingly cut and the freshly cut edge may engage into the V-shaped cut 2| during the cutting operation.

A means is provided for holding the knife support strip I3 in its various parallel positions. This means comprises an arm 22 pivotally sup ported by a pintle IS on the knife support strip I3 and extending under the foundation strip i3 This arm 22 is formed with a slot 23. A clamp screw 2 is mounted upon the foundation strip 53 and engages through a slot 23 and is provided with a clamp nut 25 which may be screwed down tight to hold the strip 22 in various posi tions. held.

The means for moving the carriage comprises a rack bar 26 mounted on the slide l3 A pinion 27 meshes with the rack bar 26 and is fixed on a shaft 28 which is rotative through a bearing 29' mounted on the body In. The shaft 28 extends to the exterior of'the box. At'its outer end it has a handle 29 by which the pinion 2! may be turned to correspondingly move the knife holding carriage.

In Fig. 8 a piece of tailors chalk I 2 is illustrated having sharpened edges [2 which are symmetrical on both sides. In Fig. 9 another piece of tailors chalk I2 is shown which has its sharpened edge I2 beveled on one side, only. t is possible to form an edge on the back as desired with the sharpening machine.

The operation of the machine is as follows:

Normally, the center of the V-shaped opening M of the knife I4 is aligned with the center of the slot I i. In this condition of the device when a piece of chalkl2' is engaged through the slot I and the handle 29 is turned first in one direction and then in the other, the knife M will reciprocate and sharpen the bottom edge of the Thus, the knife support strip is similarly chalk l2 so that the bevel on both sides is sym metrical. The shavings will fall into the drawer l2.

When it is desired that the machine sharpen the chalk with a bevel as shown in Fig. 9, then the coverplfi is loosened and removed, the wing .nut 25 is loosened and the knife support strip I3 is'shifted to anew position so that when the parts are assembled it will be in the position indicated in the dot and dash lines I 3' in Fig. 2. The clamp nut 25 is then turned down to hold the knife supporting strip in its new position. The parts are re-assembled. Now when the chalk is engaged through the slot it will be; beveled on one side only since the center of the V-shaped cutout MP is now aligned with one face of the chalk.

The device is also used as a weight, placed on the goods which is to be'marked, and the drawer or slide 15 makes it unnecessary to continually defined in the appended claims.

1. A chalk sharpening machine comprising a box-like body having a slot in its top wall through which a piece of chalk may be held, a knife holding carriage slidably mounted within said body beneath said seat, a knife for sharpening the box-like body having a slot in its top Wall through which a piece of chalk may be held, a knife holding carriage slidably mounted within said body beneath said seat, a knife for sharpening theedge of said chalk mounted on said carriage, means for moving said carriage, a drawer mounted in said body for receiving the shavings from said body, and means for holding said knife support strip in various parallel positions, whereby the knife is similarly held in various specific parallel positions relative to said slot.

3. A chalk sharpening machine comprising a box-like body having a slot in its top wall through which a piece of chalk may be held; a knife holding carriage slidably mounted within said body beneath said seat, a knife for sharpening the edge of said chalk mounted on said carriage, means for moving said carriage, a drawer mounted in said body for receiving the. shavings from said body, and means for holding said knife support strip in various parallel positions, whereby the knife is similarly held invarious specific parallel positions relative to said slot, said carriage being arranged to move parallel to said slot.

4. A chalk sharpening machine comprising a box-like body having a slot in its top wall through V which a piece of chalk may be held, a knife holding carriage slidably mounted within said body beneath said seat, a knife for sharpening the edge 'of said chalk mounted on said carriage, means for moving said carriage, a drawer mounted in said body for receiving the shavings from said body, and means for holding said knife support strip in various parallel positions, whereby the knife is similarly held in various specific parallel positions relative to said slot, said carriage being arranged to move parallel to said slot, said arms and said strips forming a parallelogram arranged.

so that the knife support strip maintains a par- 

